From nobody Tue Feb 10 00:22:26 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 65C57C6FD18 for ; Wed, 29 Mar 2023 11:54:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229703AbjC2Lyp (ORCPT ); Wed, 29 Mar 2023 07:54:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54454 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229984AbjC2Lye (ORCPT ); Wed, 29 Mar 2023 07:54:34 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id BABDC4C09 for ; Wed, 29 Mar 2023 04:54:15 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 76E411570; Wed, 29 Mar 2023 04:54:59 -0700 (PDT) Received: from localhost.localdomain (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 5E0A73F6C4; Wed, 29 Mar 2023 04:54:13 -0700 (PDT) From: James Clark To: coresight@lists.linaro.org, quic_jinlmao@quicinc.com, mike.leach@linaro.org, suzuki.poulose@arm.com Cc: James Clark , Mathieu Poirier , Leo Yan , Alexander Shishkin , Maxime Coquelin , Alexandre Torgue , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com Subject: [PATCH v3 06/13] coresight: Fix loss of connection info when a module is unloaded Date: Wed, 29 Mar 2023 12:53:19 +0100 Message-Id: <20230329115329.2747724-7-james.clark@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230329115329.2747724-1-james.clark@arm.com> References: <20230329115329.2747724-1-james.clark@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" child_fwnode should be a read only property based on the DT. If it's cleared on the parent device when a child is unloaded, then when the child is loaded again the connection won't be remade. child_dev should be cleared instead which signifies that the connection should be remade when the child_fwnode registers a new coresight_device. Similarly the reference count shouldn't be decremented as long as the parent device exists. The correct place to drop the reference is in coresight_release_platform_data() which is already done. Signed-off-by: James Clark --- drivers/hwtracing/coresight/coresight-core.c | 10 ++-------- 1 file changed, 2 insertions(+), 8 deletions(-) diff --git a/drivers/hwtracing/coresight/coresight-core.c b/drivers/hwtraci= ng/coresight/coresight-core.c index bfe1b93aca4e..12cbb68e8e1c 100644 --- a/drivers/hwtracing/coresight/coresight-core.c +++ b/drivers/hwtracing/coresight/coresight-core.c @@ -1414,13 +1414,8 @@ static int coresight_remove_match(struct device *dev= , void *data) if (csdev->dev.fwnode =3D=3D conn->dest_fwnode) { iterator->orphan =3D true; coresight_remove_links(iterator, conn); - /* - * Drop the reference to the handle for the remote - * device acquired in parsing the connections from - * platform data. - */ - fwnode_handle_put(conn->dest_fwnode); - conn->dest_fwnode =3D NULL; + + conn->dest_dev =3D NULL; /* No need to continue */ break; } @@ -1553,7 +1548,6 @@ void coresight_release_platform_data(struct coresight= _device *csdev, * is going away */ fwnode_handle_put(conns[i].dest_fwnode); - pdata->out_conns[i].dest_fwnode =3D NULL; } if (csdev) coresight_remove_conns_sysfs_group(csdev); --=20 2.34.1